The invention relates to a method for using steel slag to produce steel, which belongs to the field of metallurgy and provides a method for using steel slag to produce steel. The steel with qualified P and S contents can be produced by the method. The method for using steel slag to produce steel comprises the steps of mixing of raw materials, smelting, steel ladle refinement and vacuum refinement. When the raw materials are mixed, the steel slag, quick lime and coke are added, wherein 10-18kg of quick lime is added in one ton of steel slag, and 6-10kg of coke is added into one ton of steel slag. The contents of the [S] and the [P] of the steel produced by the method for using steel slag to produce steel are not more than 0.015 percent, and both the macroscopic test and the metallographic test of the steel reach the class I level of China. The method realizes the waste recycling of steel slag, fully utilizes iron resources, prevents resource waste, provides a new choice for the field and has wide application prospect.